In patients aged over 70 years, a non-functioning rotator cuff is an indication for a reversed shoulder prosthesis. Here we describe an 84-year-old woman with rotator cuff arthropathy and a 76-year-old man with a proximal humerus fracture, who both received a reversed shoulder prosthesis. This prosthesis decreases pain and improves the range of movement; however, the high risk of complications associated with this prosthesis should be taken into account and should be discussed preoperatively.